Well tool control mechanism



June 2, 1964 M. B. CONRAD WELL TOOL CONTROL MECHANISM s Sheet s-Sheet 1 Filed July 13, 1959 INVENTOR MARTIN B. CONRAD ATTORNEYS June 2, 1964 M. B. CONRAD WELL TOOL CONTROL MECHANISM 3 Sheets-Sheet 3 INVENTQR MARTIN B. CONRAD Filed July 13, 1959 arfiz ATTORNEYS V the upper end of the well packer or other tool.

3,135,32a V WELL TOOL CONTROL MECHANISM Martin B. Conrad, P.0. Box 1026, Downey, Calif;

Filed July 13, 1959, Ser. No. 826,841 16 Claims. (Ci. 166-1 237) The present invention relates to a ratchet control for packers or other well tools, wherein it is desired to releasably interconnect an operator member such as a packer mandrel or body to a well bore engaging device to prevent relative longitudinal movement of the operator member and the well bore engaging device as the packer or other well tool is being run into a well.

More. particularly, the invention contemplates a control mechanism for well tools which may be released responsive to rotation of the-body of the well tool relative to a well bore engaging friction device, so as to per- V mit relative longitudinal movement between the body and the friction device, wherein the control device can be re-engaged in any desired or necessary location along the body of the tool and will enable relative longitudinal movement between the body and the friction device in the opposite direction. 7

In the well tool field, it is; the common practice to provide latch mechanisms cooperable between the body of the tool and a friction device engageable with the well boreor casing wall, so as to prevent longitudinal movement between the tool body and the friction device, whereby the tool may be run into a well bore and the friction device will be caused to travel with the tool to a desiredelevation in the well, following which, rotation of the string of pipe on which the tool is run into the well,

, with consequent rotation of the tool body, will effect release of the tool body fronrthe friction device, thus to enable the tool body to be shifted longitudinally in thewell bore while the friction device remains stationary. Such relative movement in well packers for example, is employed to effect setting of well casing-engaging slips adapted to a nchor the tool at a selected point in the well bore, as well as to expand resilient packing elements into engagement with the well bore, so as to seal. off the annular space between the well tool and the well I bore.

of themandrel so as to permit the aforementioned relative longitudinal movement. v v While such previous control mechanisms of the dog type have proven to'be quite satisfactory in respect to their operating characteristics, they have encountered problems insofar as the environmental conditions under which they must operate are concerned. For example, frequently the fiuidscontained within a well contain quantities of free sand which tends to settle in the well fluids and choke 'up the control mechanism, thus preventing its effective operation when the control mechanism is run at On the other'hand, when the control mechanism is run at the lower end of the well packer or, other tool,-well fluids passing upwardly through the control mechanism tend to' carry sand or other particles intothe control mechanism where it becomes lodged and adversely affects effective operation of the control mechanism. I

Anobject of the present invention accordingly, is to provide a sand-free control mechanism through which well fluids freely pass so as to avoid the'tendency of sand to clog the control mechanism. In accordance with this Patented. June 2 1964 objective, fluid will pass freely through the control mechanism as the tool is being run'into a well with the control.

mechanism at the lower end thereof on the one hand, or on the other hand, after the tool has been set in the well and sand has had an opportunity to settle in and around the control mechanism, such sand may be readily flushed from the control mechanism thus to free the latter for effective operation.

Another objective of the invention is to provide a control mechanism which is extremely simple to manufacture and assemble, and which is extremely durable as well as trouble-free in its operation.

Yet another object is to provide a control mechanism which has one-way ratchetting engagement with thebody of a well packer or other tool so-as to prevent relative movement between the body of the tool and the control mechanism in one direction, except when the control mechanism is effectively disengaged from the mandrel, but which, due to its one-way ratchetting action, will permil: relative movement in the other direction between the control mechanism and the mandrel, whether or not the control mechanism is effectively disengaged from the on an enlarged scale with a portion of the mandrel shown in elevation, the tool being in a condition for running into a well bore. FIG. 3 is a view generally corresponding to FIG. Zbut showing the tool in a condition with the slips setin engagement with the well bore and with the packer element expanded into engagement with the well bore. FIG. 4 is a transverse sectional view as taken on the line 44 of FIG. 2, and FIG. 5 is a transverse sectional .view as taken on the line5'5 of FIG. 3. FIG. 6 is a transverse sectional view as taken on the line 6 6 of FIG. 3. FIG. 7 is a perspective view partly broken away showing the manner of assembly of, the dog-carrying collar and the dog-carrier body.

Like reference characters in the several views of the drawings and in thefollowing detailed description designate corresponding parts. v

The control'mechanism generally designated 1 is, for,

illustrative purposes, shown as embodied in aretrievable' well packer at the upper end of the packer. Such packers are of a general type well known in the art and characterized as upstrain packers. It will be understood, however, that the control mechanism of the invention has equal application to so-called set-down? packers, or to other well tools wherein it is desired to releasably interconnect for movement as a unit, a tool mandrelor body M and a wcllbore engaging device P, which is adapted to perform a desired function as arcsult of relative movement between the mandrel M and the device F.

In the illustrative packer hereof, the mandrel M is a tubular member having a large diameter bore 2' therethrough which is preferably at least equal in diameter to the diameter of the opening through the tubing or pipe string T to which the mandrel M is adapted to be con: nected as by a coupling 3. Threadedly connected to the lower extremity of the mandrel M is a bottom sub or connector 4, provided with a threaded socket5 for the reception of a downwardly extending length of tubing or pipe 6, if desired.

Interposed between the control mechanism 1 at the upper end of the assembly and the sub 4 at the lower end 3 of the assembly are, the device F previously referred to, which in the illustrative embodiment constitutes well casing-engaging friction means; laterally movable well bore engaging slip means S engageable with the. Well casing designated C for anchoring the assembly against longitudinal movement in the casing, and packer means P for engaging the well bore or casing to effect a seal between the tool and the casing.

I The casing-engaging friction means F comprises a tubular housing 7, having a plurality of longitudinally extended and circumferentially spaced slots 8 adapted to 4 retainer collar 35 having an internal flange 36 seating in a channel 37 extending circumferentially about the lower extremity of sleeve 28. The force transmitting tubular member 33 accordingly is slidable longitudinally of the sleeve 28 in a direction to effect expansion of the'packer rubber 30, but movement of the member 33 in the opposite direction is limited by the flange 36 on the split ring 35. As best seen in FIGS. 2 and 3, it will be noted that receive for radial movement a like number of casingengaging drag blocks 9, these drag blocks 9 being urged radially with respect to housing 7 as by a suitable number I of springs 10 interposed between the drag blocks 9 and the bases of the slots 8. At its lower extremity the housing 7 is connected to a slip-carrying ring 11 by a split swivel ring 12 of channel section and composed of complemental halves. The split ring 12 is engaged at opposite sides by an annular flange 13 on the lower extremity of the housing 7 and a flange 14 on the upper extremity of the slip ring 11, so as to permit freedom of rotary motion between the slips S and the housing 7.

The split ring 12 is preferably retained in assembled relation on the housing and the slip ring as by means of a retainer sleeve 15 overlying half sections of the split ring 12 and having an upwardly projecting end 16 overlying the lower extremity of the drag block receiving slots 8, so as to limit outward movement'of the drag blocks 9 upon engagement between end tongues 17 on the drag blocks and the end 16 of the sleeve 15. This sleeve 15 is secured against longitudinal displacement as by means the force transmitting member 33 is appropriately secured to the bottom sub 4 as by welding at 38, and the body or mandrel M of the device is threadedly' connected as at 39 through the bottom sub 4, so that the force transmitting member 33 and the mandrel M move longitudinally as a unit.

' While the T-heads on the slip elements 19'engage in the T-slots 21 of the slip carrying ring 11, and the dovetailed connection 24 between the wedge-shaped sections 22 of the slip elements and the cone effectively tie the slip carrying ring 11 and the cone 25 together in such a manner as to limit separation of these components, it is preferred that such means for tieing the slip carrying ring 11 and cone 25 together be supplemented by the provision of a tie sleeve 40. In'the illustrative embodiment the sleeve 40 includes an annular end 41 disposed in an internal bore 42 in the cone 25 and adapted to engage a shoulder 43 formed at the base of the bore 42. Projecting from the end 41 of tie sleeve 40 is a suitable plurality of circumferentially spaced spring fingers 44 having terof a recessed cap screw 18 threaded into the lower end of the drag block housing 7.

It will be noted that the slip means S referred to above includes a suitable plurality of circumferentially spaced slip elements 19, having T-heads 20 thereon shiftably disposed in T slots 21 in the slip-carrying ring 11, so that the slips are movable laterally of the axis of the tool into out of engagement with the well casing C. At their lower extremities the slip elements 19 are provided with wedgeshaped sections 22 provided with serrations or wickers 23 adapted to bite into the casing upon expansion of the slip elements so as to anchor the tool in a well in a manner which will hereinafter more fully appear.

' The wickered sections 22 of the slip elements 19 are provided with a dove-tailed connection as at 24 with an upper tapered end of an expander cone 25 which is adapted to shift the slip elements 19 laterally and wedge the latter in engagement with the casing upon relative longitudinal movement of the slip elements and the cone towards one another. The cone 25 has a cylindrical body section 26 which is externally threaded for the reception of a gauge ring 27, the body section 26 also being internally threaded for connection with a packer element supporting sleeve 28 slidably disposed upon the mandrel M, and preferably sealed with respect to the mandrel as by means of an O-ring seal 29.

The sleeve 28 it will be noted constitutes part of the packer means P for effecting a seal between the tool and the casing, these means P including also a resilient packminal enlargements 45 engageable in an annular recess 46 within the slip-carrying ring 11.- Accordingly, it will be noted that the enlargements 45 and the annular end 41 of the tie sleeve 40 interconnect the slip-carrying ring 11 and cone 25 against separation, but the bore 42 permits movement of these parts towards one another as'is required to permit the slips to be shifted laterally into anchoring engagement with the well casing. Such setting movement of the slips is effected responsive to movement of the mandrel M longitudinally of the casing-engaging friction means F under the control of the releasable latch or control mechanism 1.

Referring particularly to FIGS. 2, 4, andS, wherein the control mechanism of the invention is illustrated in detail. it will be noted that the mandrel M is provided with a longitudinally extended section having thereon longitudinally spaced teeth or wickers 47, which in the illustrative embodiment face upwardly with respect to the mandrel M. These teeth 47 may be helically formed on the mandrel M, or alternatively may consist of a series of axially spaced annular teeth having no lead, as is well known in the art.

Cooperatively engageable with the teeth or wickers 47 on the mandrel M is a ratchet dog means D which is provided with a suitable number of teeth 48 facing oppositely ing ring 30 disposed about the sleeve 28 and engaged at one end with the gauge ring 27. A second gauge ring 31 is slidably disposed about the sleeve 28 and engages the packing ring 30 in opposed relation to gauge ring 27, so that upon movement of gauge rings 27 and 31 towards one another the packing ring 30 will be axially foreshortened V and expanded laterally into engagement with the well casing C thus to effect a seal therewith.

to the teeth or wickers 47 on the mandrel M, and engageable therewith so as to interconnect the dog D and the mandrel M against relative movement in one direction, while enabling relative movement in the opposite direction when the dog is either out of engagement with the teeth or by reason of a ratchetting movement of the mandrel M relative to the dog D as will hereinafter be described. The dog D is carried on an arm 49a by a collar 49 extending about the mandrel M in spaced relation thereto so as to provide annular clearance as at 50 to permit the free passage of fluids between the collar 49 and the mandrel M. Diametrically opposed to the dog D and also carried by the collar 49 is a supporting arm 51. Both the supporting arm 51 and the arm 49a are provided with T-heads as at 52, 52 disposed at a slight angle to the axis of the mandrel M and in parallel relation. These T- heads 52 are slidably disposed in T-slots 53, 53 in a dog carrier body 54 of annular form which is also disposed about the mandrel M.

It will be noted that dog D effectively is a toothed portion of collar 49, and that T-heads 52 and T-slots 53 constitute means for supporting the collar on the body 54 for lateral .movement of the dog, relative to the tool mandrel or body M.

While, if desired, the dog carrier body 54 may be threadedly or otherwise interconnected with the drag block housing 7, it is preferred that the body 54- be connected to the drag block housing by means of a connector sleeve 55. It will be understood that in either case the assemblage constitutes a member disposed about the body or mandrel M.of the tool for relative rotationand longitudinal movement. Accordingly, the dog carrier body 54 isfprovidedwith an axially extended section 56, having diametrically opposed outstanding ribs 57 extending partially circumferentially therearound as best seen in FIGS.

5 and 6 while the connector sleeve 55 is provided with a ofthese parts will be permitted.

.Retainer means is provided to prevent such relative rotation when the ribs 57 and 58 are in engagement, and in the illustrative embodiment such retainer means is in the form of a cap screw 59 extending through an opening 60 in the connector sleeve 55 and threadedly engaged as at 61 in the dog carrier body 54, preferably within the zone of one of the ribs 57. I

I Resilient means is provided for biasing the dog D laterally into engagement with the mandrel M; Preferably, such resilient means comprises an annular resilient band 62, engaged as best seen in FIG. 4 with support arm 49a of dog T-head 52 and extending about the'mandrel M between the latter and arm 51 which is diametrically opposed to dog D. Preferablythe spring 62 is substantial ly relaxed when the dog teeth 48 are engaged in the mandrel wickers 47 as shown in full lines in FIG. 4, so that in order to enable rachetting of themandrel M through the' control mechanism the spring 62 is stressed to the brokenline position shown in FIG. 4.

Moreover, it will be noted that the angle of the T- heads 52 and T slots 53 on the dog D and the opposing support arm 51 and in the dog carrier 54 respectively, is

- such that a radial component of force is produced tending to urge and hold the dog D in engagement with the man- "drel wickers when the tool is in the condition shown in FIG. 2.

Furthermore, means are provided whereby the mandrel M and the dog D may be selectively disengaged so as to permit longitudinal movement of the mandrel or the tool body M when it is desired to set the slip elements 19 against the casing C and to expand the packer rubber 30 into engagement with the casing C. As best seen in FIGS. 3 and 5, the mandrel wickets 47 are interrupted by I the provision of a longitudinally extended unwickered mandrel section 63, which specifically in the illustrative embodiment of the invention is constituted by an elongated slot or way interrupting the wickets 47 and adapted to receive the dog D upon rotation. of the mandrel.

In order to assure engagement, of the dog D with the elongated slot 63, cooperative stop means are providedon the mandrel M and the dog carrier 54. Referring particularly to FIG. 5, it will be noted that elongated section 56 of dog carried 54 is provided with an arcuate channel 64 in which rides a positioning key 65, this key being slidable in an elongated key-slot 66 extending longitudinally of the tive to .dog carrier 54 to a position that the key 65 engages the opposite side of the stop projection 67willplace the? dog D in a position rotatably displaced from the slot 63 to a maximum extent. When the dog D is so displaced from the slot 63, coengaged dog teeth 48 and mandrel wickers 47 will prevent, in the case of the illustrative tool,

upward movement of the mandrel through the control mechanism 1, but downward movement of the mandrel will be permittedif necessary or desirable as the dog D ratchets over the mandrel wickets 47. Thus it is apparent that the releasable latching dog D is adapted to be re-engaged in the mandrel wickers 47 from the slot 63 irrespective of the relative longitudinal position ofthe dog D along the mandrel M within the limits'of the mandrel Wickers '47.

Furthermore, it will be noted that due to thelarge annular space 50 lying between the dog carrier collar 59 and the. mandrel M, as well as the clearance apertures 54a, fluid is free to wash through the control mechanism and flush sand or other foreign material from the control mechanism, thus to. enhance operability of the mechanism. The control mechanism 1 is further ren dered free from clogging by sand or other foreign material as a result of rotation of the mandrel.

In this connection it will be best noted upon reference to FIG. 4 that the spring 62 frictionally engages the i in FIGS. 1 and 2. Reference'to FIG. 2 will indicate that the packer means P is in a relaxed condition, and flange 36 of connector ring 35 is engaged with the shoulder formed at the lowermost side of groove 37 in packing element supporting sleeve 28,, the latter beinginten' connected to cone 25, which is in turn interconnected with the slip carrier ring 11 by tie sleeve 40.-

As shown in FIG. 2, the dog D of control mechanism 1 is engaged with the mandrel wickers .47 "so as to pre-" vent relative movement between the mandrel M and the.

friction drag means F in a 'directio n which would expand the packer element 30 and the. slips into engagement with the well bore or casing C.

This stretched-out relationship will be maintained until such time as the mandrel M is rotated .to bring the elongated slot or way 63 through the wickers 47 on mandrel M into register with the toothed portion 48 of'dog D; whereupon as shown in FIG. 3, the tool may be longitudinally foreshortened' by taking an upstrain on the mandrel M. Such upstrain will imparta force through sleeve; 33 to the packer rubber 30 which in turn is transmitted to expander coneZS, so as to wedge the slip elements 19 and more particularly the toothed heads 22 thereof into anchoring contact with the well casing C.

Upward movement of the packing means P and the slip means S is of course resisted by the casing-engaging friction means, so that subsequent to anchoring contact of the slip elements 19 with the casing C further upward strain on themandrelM through the running-in pipe or mnadrel M, A stop projection 67 is provided in the sectubing will exert a powerful wedgiug action on the slips tending to firmly set them in locking engagement with the casing. Such upward force is transmitted to the slip means S through packer rubber 30 so as toeifect a seal between the packer element 30 and the casing C.

When it is desired to release the packer tool from engagement with the well casing,- the tubing string may be lowered in the well so that the tool will again be stretched out and the packer rubber 30 and slip .elements 19 retracted from engagement with the casing C. Following lowering of the mandrel M, rotation of the mandrelwill cause re-engagement of dog Dwith wickers It will be noted that if desired or necessaryfor any reason, the mandrel M may be rotated prior to lowering the tubing string so that the toothed section 48of dog out. This feature has further advantage in the assembly and dressing of the tool prior to running the same into a well.

While the specific details of the invention have been herein shown and described, changes and alterations may be restorted to without departing from the spirit of the invention as defined in the appended claims.

I claim:

1. In a well tool having an elongated body member, an annular member encircling said body for relative longitudinal and rotative movement, one of said members having a plurality of longitudinally spaced teeth disposed thereabout in opposed relation to the other member, the other of said members having a toothed portion engageable with the teeth on said one of said members, said one of said members having a longitudinally extended smooth section interrupting the teeth thereon, means interconnecting said members for relative lateral movement, and resilient means biasing said members relatively laterally into engagement-with one another, the means interconnecting said members for relative lateral movement including a plurality of T-heads carried by one of said members, and a part on the other member having T-slots in which said T-heads are shiftably disposed.

2. In a well tool having an elongated body member, an annular member encircling said body for relative longitudinal and rotative movement, one of said members having a plurality of longitudinally spaced teeth disposed thereabout in opposed relation to the other member, the

Other of said members having a toothed portion engageable with the teeth on said one of said members, said one of said members having a longitudinally extended smooth section interrupting the teeth thereon, means interconnecting said members for relative lateral movement, and resilient means biasing said members relatively laterally into engagement with one another, the means interconnecting said members for relative lateral movement including a plurality of T-heads carried by one of said members, and a part on the other member having T-slots in which said T-heads are shiftably disposed, said resilient means including an annular spring engaged at its inner periphery with both of said members and extending between said T-heads.

3. In a well tool having an elongated body member, an annular member encircling said body for relative longitudinal and rotative movement, one of said members having a plurality of longitudinally spaced teeth disposed thereabout in opposed relation to the other member, the other of said members having a toothed portion engageable with the teeth on said one of said members, said one of said members having a longitudinally extended smooth section interrupting the teeth thereon, means interconnecting said members for relative lateral movement, and resilient means biasing said members relatively laterally into engagement with one another, the means interconnecting said members for relative lateral movement including a pair of- T-heads carried by one of said members, and a part on the other member having T- slots in which said T-heads are shiftably disposed, said T-heads and T-slots being diametrically oppositely disposed on said tool and inclined relative to the axis of the tool.

4. Control mechanism for a well tool having an elongated wickered tool body, comprising: an annular member adapted to be disposed about the tool body, an annular supporting member for said annular member, one of said members having a pair of T-heads projecting therefrom towards the other me ber having laterally. extending T-slots in which said T- heads are shiftably supported for relative lateral move-.

. ment of said members, said annular member having an internal toothed section engageable with the wickers on the body aforesaid, and means for releasably holding said annular member in engagement with said body while enabling relative lateral displacement of said body and said annular member.

5. Control mechanism for a well tool having an elongated, wickered tool body, comprising: an annular support adapted to be disposed about thetool body, a collar, means connecting said collar to said support for lateral movement of said collar relative to the tool body,

upon engagement of said toothed portion of said collar with said unwickered body portion said body is freely movable longitudinally through said collar. 7

6. Control mechanism for a well tool having an elongated wickered tool body, comprising: an annular support adapted-to be disposed about the tool body, a collar, means connecting said collar to said support for lateral movement of said collar relative to the tool body, a toothed portion within said collar engageable with the wickers on the body aforesaid, and means for urging said collar laterally to elfect engagement of said toothed portion with said body, the tool body having an elon gated unwickered portion interrupting the wickers on said body and extending circumferentially a greater dis tance than the toothed portion of said collar, whereby upon engagement of said toothed portion of said collar with said unwickered body portion said body is freely movable longitudinally through said collar, the means connecting said collar to said support also including means for creating a lateral component of force to urge the collar laterally relative to said support upon the exertion on said collar and support of a force tending to' move them axially apart.

' 7. Control mechanism for a well tool having an elongated wickered tool body, comprising: an annular support adapted to be disposed about the tool body,'a collar, means connecting said collar to said support for lateralmovement of said collar relative to the tool body, a toothed portion within said collar engageable with the wickers on the body aforesaid, and means for urging said collar laterally to effect engagement of said toothed portion with said body, the tool body having an elongated unwickered portion interrupting the wickers on said body and extending circumferentially a greater distance than the toothed portion of said collar, whereby upon engagement of said toothed portion of said collar with said unwickered body portion said body is freely movable longitudinally through said collar, the means interconnecting said support and said collar also, including a pair of diametrically spaced arms extending between said support and said collar, said means for urging the collar laterally comprising an annular spring extending between said arms for engagement with the tool body aforesaid at one side of the latter and with said collar adjacent one of said arms. t

8. Control mechanism for a well tool having an elongated wickered tool body, comprising: an annular supmber, said other mem-.

tion with said body, the tool body having an elongated unwickered portion interrupting the wickers on said body and extending circumferentially a greater distance than the toothed portion of said collar, whereby upon engagement of said toothed'portion of said collar with said unwickered body portion said body is freely movable longitudinally through said collar, the means interconnecting said support and said collar also including a pair of diametrically opposed arms carried by said collar and having T-heads thereon, said support having T-slots in which said T-heads are shiftably disposed.

9. A well tool comprising an elongated wickered body,

said body having an elongated smooth section interrupting the wickers thereon, a member disposed on said body for relative rotative and longitudinal movement of said body, an annular support rigidly connected to said member and extending about said body, cooperative stop means for limiting rotation of said body relative to said support in opposite directions, a collar disposed about said body, means connecting said collar to said support for preventing relative rotation of said support and collar and for enabling lateral movement of said collar relative to said body, and said collar having a toothed section engageable with the wickers on said body upon relative rotation between said collar and body to the limit in one direction.

10. A well packer comprising an elongated body, well bore engaging slip means, well bore engaging resilient packer means and well bore engaging friction 3 permitting lateral movement of said collar relative to said body, said'interconnecting means including a pair of circumferentially spaced arms extending between said collar and said friction means, said body having longitudinally spaced circumferentially extended wickers there on and a longitudinally extended unwickered portion interrupting said Wickers, said collar having a toothed portion internally thereof engageable with said wickers and said unwickered portion of said body selectively responsive to relative rotation of said body and said well bore engaging friction means, and means biasing said collar laterally of said body to maintain said toothed portion of said collar in engagement with said body.

11. A well packer as defined in claim comprising coengageable stop means on said body and said control mechanism for locating said toothed collar portion on said unwickered body portion upon rotation of said body. 12. In a well tool, the combination of: a cylindrical mandrel having an axial series of circumferentially extending wickers on the outer surface thereof, an annular body having a' central opening through which the mandrel extends, said body having diametrically opposed guide slots, a collar having a pair of axially extending diametrically positioned arms, each arm having a guide portion at its extending end slidably engaging one of the guide slots, respectively, one of said guide portions constituting a dog having having aplurality of teeth engageable with said wickers on the mandrel to form a ratchet connection, said guide portions and said guide slots permitting lateral movement of the collar relative to the body, an annular band encircling the mandrel and extending outside the dog-carrying arm and inside the other arm, said annular band acting resiliently to move the collar in a direction to engage the teeth on the dog with the wickers on the mandrel.

13. In a well tool, the combination of: a cylindrical mandrel having an axial series of circumferentially extending wickers on the outer surface thereof, an annular body having a central opening through which the mandrel extends, said body having diametrically opposed guide slots, a collar having a pair of axially extending diametrically positioned arms, each arm having a guide portion at its extending end slidably engaging one of the guide slots respectively, one of said guide portions constituting a dog having a plurality of teeth engageable with said wickers on the mandrel to form a ratchet connection, saidguide portions and said guide slots permitting lateral reciprocating movement of the collar relative to the body to enableratcheting of the collar and dog relative to the mandrel upon longitudinal movement of the mandrel in one direction, while preventing longitudinal movement of the mandrel in the other direction, an annular band encircling the mandrel and extending outside the dog-carrying arm and inside the other arm, said annular band acting resiliently to move the collar in a direction to engage the teeth on the dog with the wickers on the mandrel.

14. The combination set forth in claim 13 wherein the guide slots in the annular body are inclined in. a direction to facilitate lateral movement of the dog away from the mandrel.

15. In a well tool, the combination of: a cylindrical mandrel having an axial series of circumferentially extending wickers on the outer surface thereof, an annular body having a central opening through which the mandrel extends, said body having diametrically opposed inclined T-shaped slots, a collar having a pair of axially extending diametrically positioned arms, each arm having a T-head at its extending endslidably engaging one of the T-shaped slots respectively, one of said T-heads constituting a dog having a plurality of teeth'engage able with said Wickers on the mandrel to form 'a ratchet connection, said T-heads and said T-shaped slots permitting lateral reciprocating movement of the collar relative to the body to enable ratcheting of the collar and dog relative to the mandrel upon longitudinal movement of the mandrel in one direction, while preventing longitudinal movement of the mandrel in the other direction, an annular band encircling the mandrel and extending outside the dog-carrying arm and inside the other arm, said annular band acting resiliently to move the collar in a direction to engage the teeth on the dog with the wickers'on the mandrel.

16. Control mechanism for well tools having an elongated body and a member disposed about said body for relative rotation and longitudinal movement, comprising: an annular member adapted to encircle said body; a pair of arms fixed to one of said members and projecting longitudinally between said annular member and said first mentioned member, means connecting said arms to the other of said members for relative lateral movement of said annular member and said body, means for biasing said annular member laterally to cause engagement of one of said arms with said body and means for interlocking said one of said arms and said body to prevent relative longitudinal movement thereof when said one of said arms is in engagement with said body while enabling relative rotation thereof.

References Cited in the file of this patent 

16. CONTROL MECHANISM FOR WELL TOOLS HAVING AN ELONGATED BODY AND A MEMBER DISPOSED ABOUT SAID BODY FOR RELATIVE ROTATION AND LONGITUDINAL MOVEMENT, COMPRISING: AN ANNULAR MEMBER ADAPTED TO ENCIRCLE SAID BODY; A PAIR OF ARMS FIXED ONE OF SAID MEMBERS AND PROJECTING LONGITUDINALLY BETWEEN SAID ANNULAR MEMBER AND SAID FIRST MENTIONED MEMBER, MEANS CONNECTING SAID ARMS TO THE OTHER OF SAID MEMBERS FOR RELATIVE LATERAL MOVEMENT OF SAID ANNULAR MEMBER AND SAID BODY, MEANS FOR BIASING SAID ANNULAR MEMBER LATERALLY TO CAUSE ENGAGEMENT OF ONE OF SAID ARMS WITH SAID BODY AND MEANS FOR INTERLOCKING SAID ONE OF SAID ARMS AND SAID BODY TO PRE- 